Conventional armored motor vehicles attempt to moderate the effect of mines and explosive devices by using armor of a thickness that will not be penetrated by penatrators, soil, rocks or the like, or by the blast from such a mine or explosive device. Such vehicles generally have bottom surfaces parallel to the surface on which they ride and side surfaces perpendicular to the surface on which they ride. In addition, conventional vehicles may mount auxiliary items on the side of the vehicle.
When such vehicles detonate an anti-vehicle mine below the vehicle, a penetrator and/or debris above the mine is propelled upward. If the bottom of the vehicle is flat and parallel to the ground, much of the energy of the mine and any material propelled by it may hit the bottom surface perpendicular to its surface. As a result, the energy of the material and the blast is most efficiently transferred to that surface and the probability that the armor bottom will be defeated and breached is maximized. Additionally, the energy of the material and the blast being transferred to that surface may cause the vehicle itself to be propelled upward, and in some cases, leave the surface on which the vehicle runs. Furthermore, side mounting the auxiliary items may prevent the blast energy from the explosive device dissipating away from the vehicle and instead may transfer the blast energy back into the vehicle.
Traditional theory says that the blast energy of a mine, specifically a shaped mine, is directed upwards from the mine in conical shape. However, when a traditional mine is buried beneath the ground, such as, for example, under sand or soil, the blast results in a cylindrical column of sand. This column typically has less than a 5 degree deviation in any direction. This column of sand or soil can be referred to as the “soil ejecta.” Because the traditional theory relies on the concept of a conical shaped upward blast, then conventional mine protected vehicles have been designed with a relatively higher ground clearance to allow more of the blast energy to dissipate in the space above the ground before encountering the bottom of the vehicle. However, because very little energy dissipates from the soil ejecta before it contacts the vehicle, the higher ground clearance has little if any effect. Therefore, a high ground clearance may only serve to raise the center of gravity of the vehicle. This, in combination with the auxiliary items may cause the vehicle to have a higher center of gravity and may reduce the maneuverability of the vehicle.
If the bottom of the vehicle is not flat, e.g. has a V shape, energy and blast material impulses may be less efficiently transferred to the body of the vehicle. One such example of this is U.S. Pat. No. 7,357,062 to Joynt (“the '062 patent”). The '062 patent discloses a mine resistant armored vehicle with a V-shaped bottom portion of the body, and with the angle of the V between about 115 and 130 degrees. While this V-shaped bottom portion may help reduce the transfer of blast energy to the body of the vehicle, further improvements may be made considering ejecta columns that launch almost straight upwards.